The objectives of this study are to test in patients with NIDDM the hypotheses that treatment with Troglitazone 1)decreases leptin mRNA and protein in muscle and that the decrease in muscle leptin synthesis correlates with the improvement in insulin resistance; 2) lowers plasma FFA and triglyceride levels by inhibiting rates of lipolysis, and/or by increasing rates of FFA oxidation or FFA reesterification and 3) improves insulin stimulated glucose uptake (i.e., lowers insulin resistance) by lowering of plasma FFA levels.